<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .a {
            width: 100px;
            height: 100px;
            background-color: #f00;

            /* static 不定位,不会成为参照物*/
            position: static;
        }

        .a1 {
            position: absolute;
            right: 0;
            bottom: 0;
        }
    </style>
</head>

<body>

    <div class="a">
        <div class="a1">111</div>
    </div>

    <p>111</p>

</body>

</html>